Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 58A, § 9

The mailing by first class mail, postage prepaid, to the address of any appellant as given on the petition upon appeal, or to the address of his attorney or agent of record, if any, or to the usual place of business of the commissioner or of the board of assessors, or its agent or attorney of record, shall be deemed sufficient service of any pleading, motion, order, notice or process so served in respect to proceedings before the board. The board may order that further notice or notice by other means be given in any case.